Aim. The aim behind this work is: (i) to review the work on Scots pine needle litter in order to construct a model for thedecomposition process, from litterfall until a stable fraction is left, (ii) suggest a simple regulating mechanism for itssequestration of carbon. Focus will be on foliar litter of Scots pine and the genus Pinus.Discussion. The chemical composition of newly shed pine litter is in part determined by climate, e.g. mean annual temperature(MAT). Thus concentrations of nitrogen (N) are higher – and those of manganese (Mn) lower – with higher MAT.This may also influence the decomposition process. Mass loss of newly shed pine needle litter is positively influenced byclimate (e.g. MAT), as well as by N and phosphorus (P) concentrations. In the late stage (above c. 30% accumulated massloss) the influence of climate fades and those of lignin (Acid Unhydrolyzable Residue – AUR), N, and Mn are regulatingthe decomposition process. As the degradation of AUR dominates the decomposition process important parameters arethose that influence the degradation of AUR, thus N and Mn. In the humus-near organic matter limit values have beenrelated to litter Mn concentration over a wide climate gradient. Thus, the higher the Mn concentration, the further theprocess goes and the smaller the stable fraction.Conclusions. It appears that factors regulating the size of the stable litter fraction may be used as a tool on a largergeographical scale to predict carbon sequestration rates in pine forests.

New advances in air quality monitoring techniques, such as passive samplers for nitrogenous (N) or sulphurous (S) pollutantsand ozone (O3), have allowed for an improved understanding of concentrations of these pollutants in remote areas.Mountains create special problems with regard to the feasibility of establishing and maintaining air pollution monitoringnetworks, due to their complex topography and difficult access. Therefore, careful design of monitoring networks, selectionof monitoring equipment, and a reliable workforce are essential for successful mountain monitoring campaigns. TheUSDA Forest Service team, in collaboration with various partners in Europe and North America, has conducted numerousmonitoring campaigns in order to determine concentrations of O3, nitrogen dioxide (NO2), ammonia (NH3), nitric acidvapor (HNO3), and sulphur dioxide (SO2) in remote areas. These results, aided by geostatistical methodologies, haveresulted in the creation of maps that are essential for a better understanding of the distribution of various air pollutantsin the Carpathian Mountains (specifically, the Tatras, Retezat, and Bucegi ranges) in Europe; the Sierra Nevada (includingSequoia, Kings Canyon and Yosemite National Parks), the San Bernardino Mountains, the White Mountains, and JoshuaTree National Park in California; the Columbia Rivers Basin in Oregon; and the Athabasca Oil Sands Region in northernAlberta, Canada. Information on the concentrations and distribution of air pollutants which have been measured inthose areas provides an understanding of their potential risks to human health, ecosystem health and sustainability, andecosystem services.

Global patterns in forest leaf litter decomposition has been studied for decades. The result has been the formulation ofa range of models relating organic matter decay rate to climatic and litter-specific factors. It is now commonly acceptedthat the prime factor determining the litter decomposition rate on a global scale, is actual evapotranspiration (AET).However, this main effect can be seriously modified by the chemical composition of organic matter itself, resulting in largevariance at local scales. Among leaf litter components, the lignin concentration, content of water-soluble compounds,concentration of nitrogen and some other nutrients have been indicated by different authors as the major determinantsof litter decomposition rate. Unfortunately, our understanding of the factors regulating the decomposition is still far fromsatisfactory as indicated by the failure of existing models to predict properly litter decay rate in many cases. These includeespecially ecosystems from outside the temperate climate, such as boreal and wet tropical forests. The existing modelsstill cannot explain the large differences in litter decomposition rates between species, even within reasonably wellstudiedtemperate forests. My article presents several reasons for the problem of finding satisfactory litter decompositionmodels. The most important reason is the bias in studies towards temperate ecosystems, high inter-correlations betweenchemical characteristics of litter and soil, and the lack of properly designed studies on very broad geographic scales.

The intent to create Forest Promotional Complex (FPC) was introducing a new quality to Polish forestry – by taking intoaccount social preference for forests, by embracing local community needs, by compromising forest production withnature protection and to introduce the rules of sustainable and balanced forest development. Main subject of this studyis a dead wood and its ecological functions in managed forests and chosen FPC reserves. The problem of ‘naturalization’or ‘ecologisation’ of forest management is discussed.

UV radiation is a high-energy part of sunlight. Simultaneous changes in global radiation have been observed duringrecent decades. Close relationships have been found between UV intensity near ground level and the destruction of thestratospheric ozone layer known as the ozone hole. This has great consequences for all ecological systems on Earth aswell as for human health. The UV Index (UVI) was developed for the monitoring of the level and composition of UV raysreaching the lower troposphere. The paper presents changes in the UVI in Poland in the period 1996-2011. We also discussthe possible influence of changes in level of ultraviolet radiation (represented by UVI) on the frequency of skin cancer.

In the literature on the subject, evaluation of ecosystem services (ES) is regarded as a one of the important scientific problemsof nature protection, environmental economics and ecology. ES are the benefits that people obtain from ecosystems.The concept of ecosystem services is generally defined as a set of products and functions of ecosystems that benefit society.The present paper contains definitions of the most common concepts found in the literature, i.e. ecosystem services,the drivers behind these services, trade-offs and synergies, and interactions between different categories of services.

This paper defines the relationships between geographical location (which determines macroclimatic differentiation andreflects the history of the vegetation), soils (which determine hydrolytic acidity, degree of base saturation and organiccarbon content), and selected characteristics of vegetation (species richness, herb layer biomass, moss layer biomass)in one type of forest community, namely, pine forests of the Vaccinio-Piceetea class. The study area covers the majorpart of the European domain of pine forests, from 70.15°N (Norway) to 50.35°N (Poland) and from 12.02°E (Sweden)to 33.6°E (Russia). The geographical pattern shows the following correlations: (a) a rise in the number of vascular plantspecies in the herb layer as one moves from west to east and from north to south; (b) no significant relationship betweengeographical location and the biomass of the herb layer, but it is possible to divide the study area into two parts: centralScandinavia, characterized by a high level of biomass, and the rest of the area, characterized by lower herb layerbiomass; (c) a south-north increase in the standard deviation of herb layer biomass (serving also as a measure of spatialheterogeneity of the forest floor in terms of the synusial structure of the community); (d) greater biomass of the bryophyte(moss+lichen) layer in the north than in the south and in the east than in the west; (e) stability at lower latitudes ofstandard deviation for moss biomass (serving also as a measure of spatial heterogeneity of the forest floor in terms ofthe synusial structure of the community), albeit with a sharp increase north of latitude 55°N.

This paper consists of three complementary sections, preceded by a short review of various Polish publications. The discussedsections cover: I. Method of measuring down dead wood (DDW) in a forest, II. An estimation of DDW resources instands which are managed and of uneven-age, III. Suggestions for DDW management in managed forests – a look at theresults of the suggestions made 10 years ago. The first section is a review of the main assumptions of the American approachto measuring DDW. The second section presents an evaluation of DDW resources in the three Forest PromotionalComplexes of Puszcza Białowieska, Bory Lubuskie, Bory Tucholskie. An analysis of the correlations is included. The thirdand final part offers a critical look at the implementation of the recommendations made 10 years ago by the authors ofthe project. These were recommendations for, what were at that time, new principles of handling DDW in Polish forests.